GEAX
s.r.l
Chapter 6
OPERATING THE DRILLING RIG
4
14.
Repeat from step 2 if the bottom of the borehole has not been reached
obviously jumping point 12;
The kelly bar block
fig.6.2.1.1
is used to prevent the tool, in the early stages of
excavation, can twirl the axis of the kelly bar, enlarging the diameter of
excavation
fig.6.2.1.4
.
fig.6.2.1.4
In excavations following the first the block must be removed
fig.6.2.1.3
and the
verticality of the kelly bar is guaranteed only by the force of gravity
fig.6.2.1.5
.
fig.6.2.1.5 fig.6.2.1.6
Lock the half-rings with the appropriate pin A to avoid oscillations
fig. 6.2.1.6
.
